Evaluating Long-Term Oncologic Outcomes of Radiofrequency Ablation for T1a Renal Cell Carcinoma with Minimum 10 Years of Follow-Up.

Introduction: We aimed to assess long-term outcomes of radiofrequency ablation (RFA) for biopsy-proven renal cell carcinoma (RCC), with a minimum follow-up of 10 years. Methods: We retrospectively identified patients who underwent RFA for renal masses at our center between 2004 and 2014. All patients who underwent RFA for a single, unilateral renal mass measuring ≤4 cm and had a minimum follow-up of 10 years were included. Our primary outcome was RCC recurrence. Kaplan-Meier curves were used to identify recurrence-free, metastasis-free, cancer-specific, and overall survival rates. Multivariate binary logistic regression was used to determine predictors of recurrence. Results: A total of 75 patients were included in our study. Median follow-up was 131 months (interquartile range [IQR], 109-151 months). Median tumor size was 2.7 cm (IQR, 2.1-3.3 cm), and the median RENAL nephrometry score was 7 (IQR, 5-8). A total of 70.7% of pathology results showed clear cell RCC. Nine patients experienced RCC recurrence with a median time to recurrence of 54.4 months (IQR, 17.3-70.3 months). Two patients died due to metastatic RCC, and median time to death was 97.5 months (IQR, 55.8-128 months). Overall recurrence-free survival was 88%, and cancer-specific survival was 97%. No patients developed recurrence after 10 years. Univariate and multivariate regression did not identify any predictors of recurrence. Conclusion: RFA is a safe and effective treatment option for T1a RCC. Rates of recurrence and cancer-specific mortality are low at 10 years postprocedure. No patient or tumor factors were identified as predictors for RCC recurrence.